【摘要】 为探究民勤沙生植物园中蒙古沙冬青和新疆沙冬青的生态适应性，文中测定了离体脱水胁迫下两种沙冬青的叶绿素荧光参数，并对叶片功能性状特征进行了分析。结果表明：两种沙冬青叶绿素荧光参数均随脱水时间的延长而降低，蒙古沙冬青叶绿素荧光参数值均高于新疆沙冬青，说明蒙古沙冬青叶片具有较强的光合作用能力。蒙古沙冬青叶片厚度、叶干物质含量、比叶面积等功能性状指标均优于新疆沙冬青，相对水分亏缺低于新疆沙冬青，说明在同样的生境条件下，蒙古沙冬青对水分和养分的吸收效率较高，而当生境条件缺水时，叶片又表现出较强的保水性能，并能将养分储存到器官中。综合上述分析，蒙古沙冬青对民勤当地环境条件具有较强的适应性，而新疆沙冬青虽然也能在引种地生长，但适应性不如蒙古沙冬青。为了更好地适应民勤恶劣的气候条件，蒙古沙冬青主要通过增加叶片厚度、提高叶片干物质含量、提高叶片储水性等策略，延长叶片寿命，从而获得较强的竞争优势，增强对干旱、盐碱等自然条件的适应能力。更多还原

【Abstract】 Abstrac:To explore the ecological adaptability of Ammopiptanthus mongolicus and Ammopiptanthus nanus in Minqin Sandland Botanical Garden, this study measured the chlorophyll fluorescence parameters of the two species of Ammopiptanthus under in vitro dehydration stress and analyzed the functional trait characteristics of their leaves. The results showed that the chlorophyll fluorescence parameters in both species of Ammopiptanthus decreased with the prolongation of the dehydration time. The values of chlorophyll fluorescence parameters in A. mongolicus were higher than those in A. nanus, indicating that the leaves of A. mongolicus have a stronger photosynthetic capacity. The functional trait indexes such as leaf thickness, leaf dry matter content, and specific leaf area in A. mongolicus were all superior to those in A. nanus, and its relative water deficit was lower than that of A. nanus. This indicates that under the same habitat conditions, A. mongolicus has a higher absorption efficiency of water and nutrients. When the habitat is water-deficient, the leaves show a stronger water retention performance and can store nutrients in the organs. The above comprehensive analysis indicates that A. mongolicus has a strong adaptability to the local environmental conditions in Minqin. Although A. nanus can also grow in the introduced area, its adaptability is not as strong as that of A. mongolicus. In order to better adapt to the harsh climatic conditions in Minqin, A.mongolicus mainly adopts strategies such as increasing the leaf thickness, improving the leaf dry matter content, and enhancing the leaf water storage capacity to extend the leaf lifespan, thereby obtaining a strong competitive advantage and enhancing its adaptability to natural conditions such as drought and salinity.更多还原